|
|
Effect of surface finish on degradation of wood-based structural board due to influence of moisture
Kratochvílová, Erika ; Schmid, Pavel (referee) ; Petro,, Marek (referee) ; Šlanhof, Jiří (advisor)
The aim of this dissertation is the optimisation of surface finishes for application to oriented strand board (OSB) in order to increase its moisture resistance. This is a summary of research focused on experimental verification that the application of surface finish could have significant influence on reducing thickness swelling, increasing weight of OSB due to water absorption and slowing down the rise of water in OSB. There was also verified if application of surface finishes only on the cutting edges could significantly affect the penetration of water into the OSB board. Some of used test methods were based on European technical standards, but were modified in order to determine influence of surface finishes in the long term. Alternative test method was also designed and implemented. The essence of this test method was to determine how high the water can rise in OSB. The research covered 8 different types of surface finishes available on the market. The selected finishes did not require any special treatments to be applied to the surface of the OSB itself. Based on the results, a mutual comparison and evaluation of their effects was carried out.
|
|
|
Emisivity and its Impact on the Heat Conductivity
Gančev, Jan ; Hejátková, Edita (referee) ; Szendiuch, Ivan (advisor)
This work deals with the issue of emissivity and its impact on the heat dissipation.The first part describes the basics of thermal management, the issue of emissivity and its measurement. In the second, experimental part, are dedicated the emissivity values of examined specimens. These values are then used as initial conditions for the thermal simulation. In the last part are compared the measured results and the simulated results and is evaluated the impact of emissivity for the heat dissipation.
|
|
|
Hot dip galvanizing of the steel construction
Pometlo, Stanislav ; Vyplašil, Evžen (referee) ; Kubíček, Jaroslav (advisor)
This master´s thesis deals with hot dip galvanizing of steel constructions and their protection from corrosion. This work describes the origin of corrosion of steel and its corrosion in different areas and presents degreasing and pickling before hot dip galvanization. It describes possibilities of making zinc layer by the wet and draw method of hot dip galvanization. Furthermore, it puts forward reactions between zinc and iron, possible defects of the zinc layer and influence of the hot dip galvanizing on the steel constructions. The experimental part examines the influence of the hydrogen charging on the material and the time of the flux operation on the quality of layer. The work further analyses the changing of mechanical properties of steels Hardox 500 and Weldox 700 as a result of the hydrogen embrittlement during pickling by the hydrochloric acid.
|
|
| |
|
|
Testing of service life of the bolt fastening used in electron microscopy
Habarka, Ondrej ; Radoš, Jiří (referee) ; Krejsa, Jiří (advisor)
Cílem této bakalářské práce je vybrat vhodný materiál a jeho povrchovou úpravu pro šroubový spoj s jemným závitem na držáku vzorku v elektronovém mikroskopu. První částí je přehled použitelných materiálů a povrchových úprav, které jsou nemagnetické, tudíž neovlivňují elektronový paprsek v mikroskopu. Dále se práce zabývá tvorbou testovacího zařízení na testování životnosti jednotlivých vzorků závitových tyčí. Výsledkem práce je porovnání testovaných materiálů a výběr jednoho nejvhodnějšího pro reálné použití.
|
|
|
Design of measurement unit for analysis of surface materials properties
Kratochvíl, Robert ; Rozsívalová, Zdenka (referee) ; Frk, Martin (advisor)
The thesis deals with the application of laser beams for examination of material properties. The properties being examined are quality of surface finish and transmissivity of materials in the optical portion of the electromagnetic spectrum. A measuring device containing laser diodes as a source of laser beam and photodiodes for evaluation of examined phenomena serves for examination of both properties. Conversion of the signal to digital quantity and its further processing take place in a microcontroller. The data is then sent via a serial bus and a converter to a computer, where it may be saved in a user program and where the user can work with them later. The thesis contains results of reflectivity measurement of a set of metal samples with different surface finish. Transmissivity measurement was applied on a set of optical filters.
|
|
|
Architectural concrete
Novosad, Petr ; Ďurica,, Tibor (referee) ; Dulenčín, Juraj (referee) ; Klečka,, Tomáš (referee) ; Hela, Rudolf (advisor)
In the development of concrete structures and its finishes we are constantly looking for new ways to highlight the aesthetic value of the concrete. With all the possibilities of shapes, textures and colours, an architectural concrete in the hands of an architect and designer becomes a material, which can be used to express different individual and specific ideas. It is necessary to recognize and cope with these possibilities, but also the limits, which determine the properties of concrete as the proper design and implementation creates excellent finishes that are otherwise inaccessible to other materials and technologies. The theoretical part includes an extensive summary carries out a research on issues of architectural concrete and its production. From this research comes a new definition of architectural concrete and the newly redesigned and determined classes of architectural concrete with respect to the continuous development of technologies and production possibilities, rendering and surfacing. The aim of the thesis is to verify the possibilities of producing quality architectural concrete and additional treatment of the surface with respect to the desired aesthetic quality.
|
|
|
Manufacturing possibilities of modular cabinet
Valčík, Martin ; Řiháček, Jan (referee) ; Podaný, Kamil (advisor)
Bachelor's dissertation in subject Mechanical Engineering is focused on suggestion and evaluation suitable of technologies which are used for production of modular cabinet determined for switchboard cabinets STX, serial marking IP55/IK09 produced by company TVD - Technická výroba, Inc.. Technologies used for production are punching, cutting by laser or plasma beam, bending, welding MAG/MIG, WIG and spot welding. Surface finish is done by powder painting, zinc plating or anodization. In point of economical and quality view as the best procedure was choosed punching, bending, welding by MAG technology and powder painting.
|
|
|
The technology of hot-dip galvanizing
Pometlo, Stanislav ; Osička, Karel (referee) ; Mouralová, Kateřina (advisor)
This thesis deals with the technology of hot-dip galvanizing. At the beginning of this work views into the history of hot-dip galvanizing and analysis of known technologies about applying of melted zinc into the surface of material. It further describes modification for surface before application of zinc´s coating. In the next part of the work are summarized the most common corrosions of hot-dip galvanized material. The work follows up the difficultness of operation for hot-dip galvanizing device. At the end of work describes cooperation with Alka Holding s. r. o.
|
|
|
Monitoring of Solder Spreading Velocity on Metal Surface
Růžička, Miroslav ; Dušek,, Karel (referee) ; Starý, Jiří (advisor)
This work deals with flushing monitoring of spreading velocity on solder finishes Niau, OSP, Sn deposited on copper plated base material FR4 using digital cameras. After the reflow process is measured by length of spreading solder and size of wetting angle. It evaluates and compares the time dependence of velocity of spreading solder, length of solder spreading and wetting angle for NiAu, OSP, Sn finishes at different temperatures reflow and surface treatment.
|
guest ::
